20535173 has 2 divisors, whose sum is σ = 20535174. Its totient is φ = 20535172.

The previous prime is 20535169. The next prime is 20535187. The reversal of 20535173 is 37153502.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18852964 + 1682209 = 4342^2 + 1297^2 .

It is a cyclic number.

It is not a de Polignac number, because 20535173 - 2² = 20535169 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20538173) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10267586 + 10267587.

It is an arithmetic number, because the mean of its divisors is an integer number (10267587).

Almost surely, 2^20535173 is an apocalyptic number.

It is an amenable number.

20535173 is a deficient number, since it is larger than the sum of its proper divisors (1).

20535173 is an equidigital number, since it uses as much as digits as its factorization.

20535173 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3150, while the sum is 26.

The square root of 20535173 is about 4531.5751124747. The cubic root of 20535173 is about 273.8416199795.

Adding to 20535173 its reverse (37153502), we get a palindrome (57688675).

The spelling of 20535173 in words is "twenty million, five hundred thirty-five thousand, one hundred seventy-three".